Decreased nitric oxide (NO) availability is thought to be a feature of cortisol-induced hypertension in humans. 2. We hypothesized that, accordingly, the threshold for a depressor response to NO should be decreased by cortisol treatment. 3. We re-analysed data from a study of baroreflex function in normal men treated with cortisol using glyceryl trinitrate (GTN). 4. Cortisol treatment increased blood pressure and decreased the threshold dose of GTN for a fall in systolic and mean blood pressure. 5. These data support the notion that glucorticoid hypertension is associated with reduced NO bioavailability.